“Generalization of Back-Propagation to Recurrent Neural Networks”, Fernando J. Pineda1987-11-09 (; backlinks)⁠:

[independent of Werbos1988] An adaptive neural network with asymmetric connections is introduced. This network is related to the Hopfield network with graded neurons and uses a recurrent generalization of the δ rule of Rumelhart, Hinton, and Williams to modify adaptively the synaptic weights.

The new network bears a resemblance to the master/slave network of Lapedes & Farber1986 but it is architecturally simpler.